function Person(name, gender, age) {
    this.name = name;
    this.gender = gender;
    this.age = age;

    function print() {
        console.log(this.name, this.gender, this.age);
    }
}

function Sinaean() {}
Sinaean.prototype = new Person(); //Sinaean.prototype未传任何参数，所以原型上的属性都是未定义
console.log(Sinaean.prototype); //name: undefined, gender: undefined, age: undefined
//Sinaean 中未处理传入的参数
var s = new Sinaean("张三丰", '108', "男");
console.log(s.name);

console.log(typeof Number);
console.log(Number.__proto__ === Function.prototype);